Does Mood Disorder Questionnaire identify sub-threshold bipolarity? Evidence studying worsening of quality of life

- The paper offers elements of utility in the debate about screening on bipolar disorder.
- The aim was to measure the burden that may be attributed to positivity at MDQ in a community sample, and how factors such as age, gender and co-morbidity with mood, anxiety or eating disorders can interact with MDQ positivity in influencing the perception of the quality of life. The study aimed to determine whether positivity at MDQ "in itself"“in itself“ is associated with an impairment of quality of life or if such impairment is only due to the psychiatric illness expected to be more frequent in MDQ positivity. Results have supported the hypothesis that MDQ positivity identifies a spectrum of disorders of relevance even if subthreshold in respect to psychiatric diagnosis.

ObjectiveIt is debated whether the Mood Disorder Questionnaire (MDQ) can generate false positives by screening other disorders as bipolar, or identify sub-threshold bipolarity. The aim is to verify if Quality of Life (QoL) impairment in MQD positives in the community is due to MDQ positivity itself, or to psychiatric diagnosis associated with MDQ positivity (supporting the former hypothesis).MethodCommunity survey. Sample randomized after stratification of the adult population in the records of seven Italian regions. Tools: MDQ; Short Form Health Survey (SF-12); semi-structured clinical interview carried out by clinicians.ResultsPositives at MDQ show worsening QoL with an attributable burden of 2.8±1.8 lower than in MDD (5.6±3.6, p<0.001) or Eating Disorders (4.4±6.6, p<0.03) and similar to Panic Disorder (2.9±0.9, p=0.44). The burden is lower in the middle-aged (25-59 years) than in the young (18-24) (4.65±4.5 vs 2.58±2.0, p=0.007) or in the elderly (≥60) (4.12±3.2; p=0.024). In the elderly the burden is independent from comorbid psychiatric disorders.LimitationsThis is a preliminary study based on one survey not designed to test this specific hypothesis, thus its results have a heuristic value only.ConclusionsThe worsening of QoL due to positivity at MDQ is largely independent from comorbid conditions, supporting the hypothesis that MDQ positivity identifies a specific area of suffering that is “subthreshold“ to the psychiatric diagnosis, and relevant for public health.